a 1.9kg ball of putty moving to the right has a head -on inelastic with 1.3 kg putty ball moving to the left , if the combined blob doens;t move just after the collision, what can you conclude about the relative speeds of the balls before they collide?

The relatave speeds of the balls are inversely prop to the mass ratios:

ball going to right has 1.3/1.9 of the speed going to the left.

1.9

To determine the conclusion about the relative speeds of the balls before they collide, we can use the principle of conservation of momentum. According to this principle, the total momentum before a collision is equal to the total momentum after the collision in the absence of external forces.

Let's denote the mass of the first ball as m1 (1.9 kg) and the mass of the second ball as m2 (1.3 kg). The velocity of the first ball before the collision is v1, and the velocity of the second ball before the collision is v2. Since the balls have an inelastic collision and stick together afterward, the combined blob doesn't move.

The principle of conservation of momentum can be expressed as:

(m1 * v1) + (m2 * v2) = 0

Since the combined blob doesn't move after the collision, the final velocity of the combined blob is 0. Therefore, after the collision, the total momentum is:

(m1 + m2) * 0 = 0

We can rearrange the equation to solve for the final velocity of the combined blob:

m1 * v1 + m2 * v2 = 0
v1 = -((m2 * v2) / m1)

From this equation, we can deduce that the relative speed of the balls before they collide is determined by the ratio of their masses (m2 / m1). Since the masses are given as m1 = 1.9 kg and m2 = 1.3 kg, we can conclude that the magnitude of the relative speed of the balls before the collision is greater than 1.3 kg / 1.9 kg, or approximately 0.684.

However, we cannot determine the exact values of v1 and v2 without further information about the collision, such as the duration over which the collision occurs.